Oil filter induced low oil pressure
Ok this truck makes the second in the last couple months that has come a complaint of check engine light on and oil pressure dropping lower than normal or all the way to zero on the dash gauge. Both trucks set oil pressure sensor performance codes. With oil sending units being extremely common failures, and the ease of changing them they where replaced along with the filter screen. However the issue still occured, the issue on both was resolved by changing the oil filter.
Both had been recently serviced and each had a different brand filter, one AC Delco and one Valvoline. So my question is, were these just fluke random occurrences, or is this a common issue on this engine? Tech next to me said he thought there was a bulletin on Delco filters causing this but I have not researched it yet as this was resolved right before the end of day.
There is a bulletin, I have experienced the issue with several brands, however I am guessing the OEM is the same for each of them. I see this a few times a year, now the process is oil change before sensor.
I believe that is going to be added to my procedure as well.
Bradley Quiring has described how an alternative Delco filter gives more than 10 psi increase in this application over the specified oil filter.
Thats what we experienced. The last truck went from 20 psi at hot idle to 35 psi at hot idle. We stock Champ oil filters which I believe are an economy level filter.
Thanks, if I get time I will pull the bulletin and read through it.
I have also seen the screen filter clog quickly again after changing it, depends on how dirty the customer engine is, I normally pull it and change the screen again. But good to know about the oil filter issue as well
Hi this engine need overhoul .
I did one a couple weeks ago that was the exact same way. My question was under code set critera it dosnt give the exact number that it wants to see at a certaint RPM, that would be helpful in my opinion. Mine was also a Valvoline oil change.
On this vehicle Alldata gave pressure specs for 1000, 2000, and 3000 rpm. If memory serves me it was 24 psi, 35 psi, and 38psi but I may be off a smidge. But yeah the code set criteria stated it sets if pressure is so many psi below expected pressure, or so many psi above expected pressure.
Ok, I will have to look some more then. Thanks for the responce. 👍
Plugged oil filter is the #1 cause of low oil pressure seen here. Then it bypasses and plugs the screen, damages lifters in my opinion, starves the engine of proper oil pressure and spins cam bearings (also my opinion). Pattern is customers that do extended oil changes.
We change the screen anytime we change pressure sensors and so far I have not found a plugged screen. But we also have not seen a 5.3 where a lifter roller locked up and destroyed a cam lobe either. Had 2 cars in today where both complained about having to add oil, one had went 5000 miles on their oil change and the other had gone 8000 miles
Wonder if they are using good filters or a cheaper brand? We tend to use napa gold on the newer trucks that require dexos.
These engines are notorious for oil pressure problems, with the RPO LC9 being the worst for some reason. the oil pressure sensor/VLOM filter is the most common cause and will lower the oil pressure within a few minutes of running. The next “unofficial“ fix is to replace the standard PF48 oil filter with a PF63. The 63 has less back pressure and can raise the gauge about 10 psi and is safe to use…